Calculus retrieving/removing device and method

ABSTRACT

A method of retrieving calculus in a renal pelvis of a living body involves positioning an enclosure in the renal pelvis, creating convection in the renal pelvis by introducing liquid into the renal pelvis from outside the living body to lift the calculus from a surface of the renal pelvis, retrieving the calculus in the renal pelvis by creating a vacuum in the enclosure while the enclosure is located in the renal pelvis so that the calculus are drawn into the enclosure, wherein the vacuum also draws the liquid into the enclosure, and withdrawing the enclosure from the renal pelvis while the calculus is in the enclosure.

TECHNICAL FIELD

The present invention generally pertains to methods and systems forretrieving/removing a mass from a human body. More specifically, theinvention involves methods and systems for retrieving/removing calculus(e.g., stones) from a portion of a human body such as the renal pelvisor the ureter.

BACKGROUND DISCUSSION

The term urinary calculus (e.g., kidney stones and ureteral stones)refers to masses or stones, typically solid particles, that form in thehuman body and are located in the kidneys and/or the ureter. They canexhibit a variety of chemical compositions including calcium oxalate,calcium phosphate, uric acid, cystine, and struvite.

Stone disease (e.g., kidney stones and ureteral stones) is a relativelycommon urological disorder. The presence of calculus in the body canmanifest itself in a variety of ways and can produce a number of medicalailments. For example, the presence of calculus in the renal pelvis(kidney) can cause blood in the urine, urinary obstruction, infection,and various degrees of pain ranging from vague frank pain to much moresevere pain not capable of being relieved through general painmedication. The presence of stones or calculus in the ureter can resultin relatively severe side and back pain, pain below the ribs, and painthat sometimes spreads to the lower abdomen and groin, as well as painduring urination and hematuria.

Fortunately, many calculus or stones pass out of the body withoutrequiring any specific medical intervention. In those situations wherethe calculus does not naturally pass out of the body, a medicalprocedure may be required. Known medical procedures typically fall intothree categories.

In the past, three main treatments have been used to address calculus orkidney stones. These include shock wave lithotripsy (ESWL),transurethral lithotripsy or ureteroscopy (URS), and percutaneousnephrouretero lithotripsy (PCNL) which is sometimes also referred to aspercutaneous nephrolithotomy (PCN).

Shock wave lithotripsy is performed as an extracorporeal treatment. Thistreatment utilizes a machine called a lithotripter that operates bydirecting ultrasonic or shock waves from outside the body, through theskin and tissue, and at the calculus or stones. Repeated shock wavesapply stress to the stones, eventually breaking the individual stonesinto smaller pieces which can more easily pass through the urinary tractin urine. One benefit associated with shock wave lithotripsy is that itis a rather simple procedure. But it has been found that there is arelatively high rate of kidney stone recurrence following shock wavelithotripsy.

Transurethral lithotripsy or ureteroscopy represents one suchalternative form of treatment. This treatment involves the use of smallfiber optic instrument called a ureteroscope which allows access to thecalculus in the ureter or kidney. The ureteroscope can be a rigidureteroscope or more commonly, a flexible ureteroscope. The ureteroscopeallows the medical professional to visualize the stone as theureteroscope moves along the ureter or enters the kidney by way of thebladder and the urethra. Once the calculus is visualized, a basket-likedevice is used to grasp smaller stones and remove them. If the calculusis excessively large to remove as a single piece, it can be broken intoa smaller pieces by using laser energy.

The third form of treatment is percutaneous nephrolithotomy. Thisprocedure is often used with relatively larger calculus that cannot beeffectively treated with either ESWL or URS. Percutaneousnephrolithotomy involves nephrostomy; making an incision at theappropriate location, needling by paracentesis needle, positioning aguide wire through the paracentesis needle's lumen into the kidney underradiographic guidance, and then expanding perforated site. A nephroscopeis then moved into the kidney via nephrostomy to visualize the calculus.Fragmentation of the calculus can be performed using an ultrasonic probeor laser.

Though these procedures have been commonly used, they are susceptible ofcertain short comings. For example, the ESWL procedure results in arelative large number of small calculus or small stones, while otherprocedures require a relatively narrow and long access route or aredifficult to implement due to the inability to accurately capture thestones. In addition to, many crush pieces should be removed one by onein URS and PCNL procedure. The procedure time can also be excessivelylong, and can result in a relatively low “stone free rate.” Therecurrence rate can also be unacceptably high. And the potential patientcomplications (e.g., ischemia of the ureter, obstruction of ureter,back-flow and/or high-stress to the renal pelvis, infection of theurinary tract, and other possible injury) can be undesirably high.

SUMMARY

According to one aspect, a method for removing a calculus located in alumen of a ureter involves moving a ureteral plug part of an elongatedmember in the lumen of the ureter toward the calculus located in thelumen of the ureter and past the calculus so that the ureteral plug partis positioned beyond the calculus. The ureteral plug part is positionedat the distal end portion of the elongated member, and the elongatedmember also includes at least one irrigation port positioned between theureteral plug part and a proximal end portion of the elongated member,with the ureteral plug part being sized so that the outer surface of theureteral plug part is spaced from the inner surface of the lumen in theureter. The method additionally involves occluding the lumen in theureter while the ureteral plug part is positioned beyond the calculus,washing away the calculus in the ureter in a direction away from theureteral plug part by discharging fluid from the irrigation port intothe lumen and toward the calculus, releasing the occlusion of the lumenin the ureter, and withdrawing the elongated member, inclusive of theureteral plug part lumen in the ureter, from the lumen of the ureter.

According to another aspect, a method for removing a calculus located ina lumen of a ureter comprises positioning an elongated drainage tube inthe lumen of the ureter, with the elongated drainage tube including anirrigation port and an operation part, and the elongated drainage tubebeing positioned in the ureter so that the ureteral plug part and theirrigation port are positioned distally of the calculus while theoperation part of the elongated drainage tube is positioned proximallyof the calculus. The method also involves occluding the lumen in theureter, washing the ureteral lumen by discharging fluid from theirrigation port toward the calculus, and releasing the occlusion of thelumen of the ureter and uncoupling the operation part from the ureteralplug.

In accordance with a further aspect, a method for removing a calculuslocated in a lumen of a ureter includes moving a ureteral plug partalong the lumen in the ureter, wherein the ureter is connected at oneend to a kidney and at an opposite end to a bladder, and wherein theureteral plug part is moved in the lumen of the ureter from the bladdertoward the kidney so that the ureteral plug part is moved to a positionbetween the calculus and the kidney. The method additionally involvesoccluding the lumen of the ureter at a location in the lumen at whichthe ureteral plug part is located, introducing fluid into the lumen ofthe ureter between the location of the occlusion and the calculus sothat the fluid washes the calculus toward the bladder, and releasing theocclusion of the lumen in the ureter.

Other features and aspects of the calculus retrieving/removing deviceand method disclosed here will become more apparent from the followingdetailed description considered with reference to the accompanyingdrawing figures in which like elements are designated by like referencenumerals.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic illustration of a portion of the human anatomy,including the urinary tract.

FIG. 2 is a schematic cross-sectional view of a kidney.

FIG. 3 is a longitudinal cross-sectional view of a calculusremoving/retrieving device representing one example of the devicedisclosed here used to carry out an aspect of the disclosed method.

FIG. 4 is a cross-sectional view of a check valve used in the calculusremoving/retrieving device shown in FIG. 3.

FIG. 5 is a cross-sectional view of the check valve shown in FIG. 4,with the distal portion of a syringe moving the check valve to the openposition.

FIG. 6 is a perspective view of the end portion of the rubber plug usedin the check valve shown in FIGS. 4 and 5.

FIG. 7 is a schematic illustration of the calculus removing/retrievingdevice show in FIG. 3 positioned in the lumen of a ureter (ureterallumen).

FIG. 8 is a schematic illustration of the calculus removing/retrievingdevice shown in FIG. 7 positioned in the ureteral lumen while beingguided by a guide wire under observation with an ureteroscope.

FIG. 9 is a schematic illustration of the calculus removing/retrievingdevice used with an ureteroscope.

FIG. 10 is a schematic illustration of another embodiment of thecalculus removing/retrieving device disclosed here by way of example andpositioned in a ureteral lumen.

FIG. 11 illustrates the calculus removing/retrieving device shown inFIG. 10 after separation of a proximal end portion to result in aureteral stent.

FIG. 12 is a schematic illustration of the elongated member shown inFIG. 11 serving as a ureteral stent extending between the kidney and thebladder.

FIG. 13 is a schematic illustration of another embodiment of thecalculus removing/retrieving device disclosed here by way of example andpositioned in a ureteral lumen.

FIG. 14 illustrates the calculus removing/retrieving device shown inFIG. 13 depicting a different operational aspect of the device.

FIG. 15A is a schematic illustration of another embodiment of theelongated member disclosed here by way of example that includes anaspiration part.

FIG. 15B is a schematic illustration of the elongated member shown inFIG. 15A aspirating a ureteral lumen.

FIG. 16 is a schematic illustration of another embodiment of theelongated member disclosed here by way of example, wherein the calculusremoving/retrieving device is specifically configured for use in therenal pelvis.

FIG. 17 is a schematic illustration of the elongated member shown inFIG. 16 positioned in a renal pelvis.

FIG. 18 is a schematic illustration of a renal pelvis illustrating anaspect of the method in which calculus in one portion of the renalpelvis are moved to another portion of the renal pelvis.

FIG. 19 is a schematic illustration of the calculus removing/retrievingdevice shown in FIG. 16 positioned in the renal pelvis after thecalculus has been moved from the one portion of the renal pelvis to theother portion of the renal pelvis.

FIG. 20 is a schematic illustration of the procedure that the volume of“pulling back the ureteroscope” and “additional pouring irrigationwater” is continuously adjusted to be equal (i.e., the same) to avoid arise or increase in the intra-renal pressure.

FIG. 21 is a schematic cross-sectional view of a calculusremoving/retrieving device according to a further embodiment disclosedhere by way of example, wherein the calculus removing/retrieving devicehas particular application for use in a renal pelvis.

FIG. 22 is a schematic illustration of the calculus removing/retrievingdevice shown in FIG. 21 depicting a different operational aspect of thedevice.

FIG. 23 is a schematic illustration of the calculus removing/retrievingdevice shown in FIGS. 21 and 22, depicting the convection producedduring operation of the device.

FIG. 24 illustrates the calculus removing/retrieving device shown inFIGS. 21 and 22 positioned in a renal pelvis and producing convection.

FIGS. 25A-25C are illustrations of a rubber seal check valve that can beused as an example of the check valve for the calculusremoving/retrieving device shown in FIGS. 21 and 22.

FIG. 26 illustrates duck bill-type check valves that can be used as anexample of the check valve for the calculus removing/retrieving deviceshown in FIGS. 21 and 22.

FIG. 27 is an illustration of an impeller.

DETAILED DESCRIPTION

Before discussing details and aspects of the methods and calculusremoving/retrieving device described here as examples of the inventiondisclosed here, reference is made to FIGS. 1 and 2 to describeanatomical aspects of relevant aspects of a human body, including theurinary tract. Referring first to FIG. 1, the urinary tract includes thekidney 200, the bladder 202 and the ureter 204. The ureter 204 extendsbetween and is connected to both the kidney 200 and the bladder 202. Theureter 204 possesses a lumen (ureteral lumen) that communicates with theinterior of the kidney 200 and the interior of the bladder 202. Theterminal end portion of the ureter penetrates through the muscle wall ofbladder, and opens into the inside of the bladder at the ureteralorifice. Additional features illustrated in FIG. 1 include thephysiological stricture of the ureter 204, the ureteropelvic junction(UPJ) 208, the iliac artery crossing 210 and the ureterovesical junction(ureter bladder junction (UBJ)) 212.

FIG. 2 illustrates additional details associated with the kidney 200.The identified parts of the kidney in FIG. 2 include the renal pelvis220, the renal vein 222, the renal artery 224, several of the minorcalyces 226, one of the major calyx 228, the cortex 230, the capsule232, the papilla of medulla 234 and the medulla (pyramids) 236.

The methods and devices disclosed here for removing/retrieving calculushave particularly useful application to address calculus located in theureter 204 (ureter stones) and calculus located in the renal pelvis 220(kidney stones).

A first embodiment of the calculus removing/retrieving device disclosedhere is illustrated in FIG. 3. The calculus removing/retrieving device30 includes an elongated member 31 having a ureter plug part 32 and anirrigation port or irrigation nozzle 34. The ureter plug part 32 isconfigured to be expanded to a relatively larger size as shown in FIG. 3and contracted to a relatively smaller size. The ureter plug part 32 isthus configured to be enlarged and reduced in size. In the illustratedembodiment disclosed by way of example, the ureter plug part 32 is aninflatable balloon. The ureter plug part 32 is expanded by introducing afluid into the interior of the ureter plug part 32, and the ureter plugpart 32 is contracted by allowing the fluid to empty from the ureterplug part 32. The fluid can be water, air, contrast medium, etc.

Fluid is introduced into the ureter plug part 32 and is expelled fromthe ureter plug part 32 by way of a ureter plug part lumen 38. One endof the ureter plug part lumen 38 opens to the interior of the ureterplug part 32 and the opposite end of the ureter plug part lumen 38 isprovided with a check valve 40. The check valve 40 can be of any knownconstruction. One example is illustrated in FIG. 4.

The check valve in FIG. 4 includes a movable rubber plug 42 and a spring44, both of which are positioned in, and enclosed within, a housing 46.The housing 46 includes an open end 49 at one end (the right end inFIGS. 4 and 5) and a closed end (equipped with a through hole) at theopposite end (the left end in FIGS. 4 and 5). The spring 44 normallybiases the rubber plug 42 in the direction of the open end 49 and intosealing engagement with the valve seat 48 of the housing 46. FIG. 4illustrates the normally closed position of the check valve 40 in whichthe rubber plug 42 is in sealing engagement with the valve seat 48 ofthe housing 46. The check valve 40 is configured to be opened by movingthe rubber plug 42 against the biasing force of the spring 44 (i.e., tothe left in FIGS. 4 and 5). In the illustrated embodiment, this isaccomplished by inserting the tip end portion of a syringe 50 into theopen end 49 of the housing 46. Inserting the tip end portion of thesyringe 50 into the open end 49 of the housing 46 causes the tip end ofthe syringe 50 to contact the rubber plug 42. Pushing the syringe 50further inward overcomes the biasing force of the spring 44 and urgesthe rubber plug 42 out of engagement with valve seat 48. This thus opensthe check valve 40. Next, by forwardly moving the plunger 52 within thebarrel of the syringe, air in the barrel of the syringe is introducedinto the ureter plug part lumen 38 to thus inflate or expand the ureterplug part 32.

FIG. 6 illustrates the end portion of the rubber plug 42 that faces andis contacted by the tip end of the syringe 50. As illustrated, the endportion of the rubber plug 42 possesses a forked configuration in whichthe center region is cut-out (i.e., a U-shaped cut-out). This allows thefluid inside the barrel of the syringe 50 to be discharged from the tipend of the syringe when the tip end of the syringe is in contact withthe rubber plug 42. After an appropriate amount of fluid is introducedinto the ureter plug part 32 to expand or inflate the ureter plug part32, the syringe 50 can be disengaged from the check valve 40. At suchtime, the spring 44 biases the rubber plug 42 back into engagement withthe valve seat 48 to close the check valve 40. The ureter plug part 32thus remains in the expanded or inflated state. Naturally, the ureterplug part 32 can be contracted by the reverse method to that describedabove.

The irrigation lumen 36 is connected to a fluid source 60. The fluidsource 60 is preferably a liquid, more preferably saline. In a morepreferable example, the cross-sectional area of the irrigation lumen 36is larger than the cross-sectional area of the ureter plug part lumen38, because efficient irrigation needs a relatively high flow rate, butefficient inflation does not require such a high flow rate.

FIG. 7 is an illustration of the calculus removing/retrieving device 30positioned in the lumen 205 of the ureter 204. In use, the calculusremoving/retrieving device 30 is introduced into the ureteral lumen 205by way of the bladder and the urethra. That is, with the ureteral plugpart 32 in the contracted or deflated condition, the tip end of thecalculus removing/retrieving device 30 is introduced into the urethra,is advanced through the bladder 202 and is moved along the ureter 204.The calculus removing/retrieving device 30 is moved in the forwarddirection in the ureter 204 to position the ureteral plug part 32 at aposition beyond the calculus or stone(s) 300 to be removed. That is, thecalculus removing/retrieving device is moved within the ureter 204 sothat the ureteral plug part 32 moves past the calculus or stone(s) 300to position the ureteral plug part 32 at a position between the renalpelvis (kidney) and the calculus 300.

After the ureteral plug part 32 is positioned at the appropriate placein the ureter, the ureteral lumen 205 is occluded. This occlusion isaccomplished by inserting the tip end portion of the syringe 50 into theopen end 49 of the valve 40 to open the valve 40, forwardly pushing theplunger 52 in the barrel of the syringe 50 to deliver fluid from thesyringe barrel to the ureteral plug part 32 by way of the valve 40 andthe ureteral plug part lumen 38, thus causing the ureter plug part 32 tooutwardly expand as described above so that the outer surface of theexpanded ureteral plug part 32 contacts the inner surface of theureteral lumen 205. More specifically, the expanded ureteral plug part32 preferably contacts the inter wall of the ureteral lumen 205 along acontinuous circumference of the ureteral plug part 32. The expanded orinflated ureteral plug part 32 is an example of an occlusion means foroccluding the ureteral lumen 205.

Once the ureteral lumen 205 is occluded as shown in FIG. 7, fluid(liquid) is discharged from the irrigation port 34 to wash the ureterallumen 205. The fluid discharged from the irrigation port 34 flowstowards the calculus 300 and then continues flowing towards the bladder.The fluid discharged into the ureteral lumen 205 by way of theirrigation port 34 carries away (flushes or washes away) the calculus300 towards the bladder. The fluid thus washes away or flushes thecalculus 300 to remove the calculus 300 from the ureteral lumen. Thecalculus 300 can flow out of the bladder with the urine stream naturallybecause the urethral lumen size is larger than the size of the calculus300 and the ureteral lumen 205. After the discharge of the fluid iscompleted (i.e., after the calculus 300 has been washed away), theureteral plug part 32 is contracted or deflated by simply pressingagainst the rubber plug 42 in the check valve 40 so that the rubber plug42 lifts off the valve seat 48, thus allowing fluid to leave theureteral plug part 32. Once the ureteral plug part 32 is deflated orcontracted, the ureteral lumen 205 is no longer occluded. It is nowpossible to withdraw the elongated member 32 out of the ureteral lumen(i.e., away from the kidney and towards the bladder).

If the calculus or stones 300 in the ureter 204 are many, it is possibleto carry-out the above-described operation in a step-wise manner. Forexample, when moving the ureteral plug part 32 within the ureter 204toward the kidney, the ureteral plug part 32 can be moved past some ofthe calculus or stones 300, whereupon the above-described operation iscarried out to flush or wash away the calculus or stones 300 downstreamof the ureteral lumen 205. After such flushing, the ureteral plug part32 is moved once again in the forward direction toward the kidney pastmore of the calculus or stones 300. This is repeated until all of thecalculus or stones 300 have been washed out of or removed from theureter 204. As another example or possibility, the fluid can bedischarged from the irrigation port 34 while rotating the calculusremoving/retrieving device 30. In this way, it is possible to moreevenly discharge fluid with respect to the calculus or stones 300.

It is also possible to use the expanded or inflated ureteral plug part32 as a “rake” to rake-out the calculus or stones 300 from the ureterand thus assist the washing or flushing by the fluid. After washing, orduring washing, the partly expanded or inflated ureteral plug part 32 ismoved rearwardly within the ureter 204 in the direction toward thebladder 202. The ureteral plug part 32 is moved in this way while theureteral plug part 32 is in the expanded or inflated state so that theexpanded or inflated ureteral plug part 32 pulls along or rakes thecalculus or stones 300.

As a part of the operational procedures described above, it is alsopossible to perform lithotripsy to break-up the calculus or stones 300using an acoustic pulse. The use and effect of lithotripsy is known inthe art and so a detailed discussion is not set forth here. Thelithotripsy procedure can be performed after the ureteral plug part 32is moved/positioned beyond the calculus or stones 300, but beforeexpanding the ureteral plug part 32. Alternatively, the lithotripsyprocedure can be performed after the ureteral plug part 32 ismoved/positioned beyond the calculus or stones 300 and after expandingthe ureteral plug part 32, but before discharging fluid from theirrigation port or nozzle to flush or wash the ureteral lumen 205 withthe discharged fluid. It is further possible to perform lithotripsy tobreak-up or fragment the calculus or stones before moving the ureteralplug part 32 into the ureter 204.

FIG. 8 illustrates another aspect of the disclosure here involving thecalculus removing/retrieving device, and associated method, shown inFIGS. 3-7. The calculus removing/retrieving device 30 may be usedtogether with a guide wire 62. The calculus removing/retrieving device30 may be appropriately configured in the normal way to accommodate theguide wire 62, for example by inserting the calculus removing/retrievingdevice in the direction toward the ureter 204 across the UBJ 212 with aguide wire 62. The guide wire 62 is then used to guide the calculusremoving/retrieving device 30 to the desired location in the ureter.FIG. 9 illustrates that the calculus removing/retrieving device 30 canbe used with an ureteroscope 64. This ureteroscope 64 possesses a knownconstruction and so a detailed discussion of associated features willnot be described in detail. In this version of the calculusremoving/retrieving device 30 and method, the ureteroscope 64 can be arigid ureteroscope.

In use, the guide wire 62 is appropriately introduced into the body(e.g., through the urethra) and advanced through the bladder, ureteralorifice and into the ureter 204, and the tip of the guide wire 62 entersthe kidney 200 through the ureter 204. The ureteroscope 64 is theninserted into the ureter 204 along the guide wire 62. The calculusremoving/retrieving device 30 is inserted into the instrument lumen inthe ureteroscope 64, and then debouched into the ureter 204 from the tipor open end of the instrument lumen of the ureteroscope 64.Alternatively, the calculus removing/retrieving device 30 may beinserted into the instrument lumen in the ureteroscope 64 first. Thenthe calculus removing/retrieving device 30 and the ureteroscope 64 areinserted into the ureter 204 along the guide wire 62 together. Theureteroscope 64 provides a mechanism for visually observing the calculusin the ureter to appropriately position the calculus removing/retrievingdevice relative to the calculus, including advancing the ureteral plugpart 32 to a position beyond the calculus (i.e., between the kidney andthe calculus). The procedure discussed above for discharging fluid(liquid) into the ureter to wash or flush the ureter lumen and thecalculus or stones is then followed.

In the operation discussed above, after the calculus removing/retrievingdevice 30 is properly positioned in the ureter 204, the ureteroscope 64can be pulled-back in the rearward direction to a position outside theureter 204 (e.g., to a position in the bladder) or the ureteroscope 64can be pulled-back so that it is removed from the living body. That is,the ureteroscope 64 can be pulled-back to a position outside the ureter204 or outside the body before discharging fluid from the irrigationport or nozzle to flush or wash the ureteral lumen 205 with thedischarged fluid. As an alternative, after the calculusremoving/retrieving device 30 is positioned at the desired place in theureter 204, the ureteroscope 64 can be kept at its position, andpulled-back to outside the living body concurrently with the dischargingof the fluid from the irrigation port or nozzle to flush or wash theureteral lumen 205 with the discharged fluid. In this latter situation,the ureteroscope 64 is pulled-back together with the calculus and theliquid.

As discussed above, the guide wire 62 may be used to help guide thecalculus removing/retrieving device 30 and/or the ureteroscope 64. Theguide wire 62 can also be used to change and keep the ureter 204 shapeas a straight shape. The guide wire 62 can also be used to open theureteral orifice before the washing to facilitate draining of the fluidafter the washing begins. Such shape's changes help create or maintain adrainage passage easily through the ureteral lumen 205.

FIGS. 10-12 illustrate another variation on the calculusremoving/retrieving device described above. The calculusremoving/retrieving device 30′ is similar to the calculusremoving/retrieving device 30 described above, except that a distal end35 of the elongated member 31 is extended and possesses an open distalend 37. In addition, the proximal end portion of the elongated member 31is configured so that the proximal-most end portion (operation portion)33 is separable from the remainder of the elongated member 31 by way ofa separable connector 39. The operation portion or proximal-most endportion 33 of the elongated member 31 is the part that is grasped andoperated by the operator or medical professional.

A proximal end portion of the elongated member 31 and the proximal-mostend portion (operation portion) 33 are connected by the separableconnector 39 temporarily. That is, the separable connector 39 is atemporary connector. By way of example, the separable connector 39 canconsist of weak fusion splicing or fitting parts (e.g., convex andconcave). If the cross-sectional surface of the remainder of theelongated member 31 at the separable connector 39 side is forced in theforward direction toward the kidney by a pusher force existing in theproximal-most end portion (operation portion) 33 additional lumen, theelongated member 31 and the proximal-most end portion (operationportion) 33 can be separated rather easily.

In use, the calculus removing/retrieving device 30′ is introduced intothe ureter 204 in a manner similar to that described above (e.g., by wayof the urethra and the bladder, and with or without the aid of a guidewire 62 and/or the ureteroscope 64). By virtue of the open distal end37, the calculus removing/retrieving device 30′ can serve as a ureteralstent or drainage tube prior to carrying out the medical procedure. Thatis, after the calculus removing/retrieving device 30′ is positioned inthe ureter 204 at the intended or desired location, the open ends of thecalculus removing/retrieving device 30 creates or allows urinary flowthrough the calculus removing/retrieving device 30′. Urinary flow canthus continue while waiting to begin the medical procedure or operation(i.e., while waiting to begin flushing or washing with the liquid).

In addition, using the calculus removing/retrieving device 30′ shown inFIG. 10, after the calculus removal/retrieval method is carried out asdescribed above, the proximal-most end portion or operation portion 33of the elongated member 31 can be separated from the remainder of theelongated member 31 at the separable connector 39. Following thisseparation, the proximal end portion of the elongated member 31 is openand positioned in the bladder 202, while the open distal end portion 35remains positioned in the renal pelvis (kidney). Thus, following themedical procedure or operation to remove/retrieve the calculus, theelongated member 31 remains in place and operates as a drainage tube orureteral stent that maintains urinary flow. Thus, this embodiment of thecalculus removing/retrieving device 30 illustrated in FIGS. 10-12provides a mechanism for maintaining urinary flow both before and afterthe calculus removing/retrieving procedure.

FIGS. 13 and 14 illustrate calculus removing/retrieving devicesrepresenting other examples of the device (and associated method)disclosed here. These embodiments of the calculus removing/retrievingdevice are the same as described above and illustrated in FIG. 3, exceptthat the device is outfitted with a ureter wall pushing element tomaintain a space or flow path for the fluid (liquid) discharged from thecalculus removing/retrieving device as well as the calculus being washedaway by the fluid. In the embodiment illustrated in FIG. 13, thecalculus removing/retrieving device 30″ includes a ureter wall pushingelement 66 in the form of two spaced apart projections 68 affixed to theelongated member 31 and projecting away from the elongated member 31into direct contact with the inner surface of the ureteral wallsurrounding the ureteral lumen 205. The pushing element 66 is configuredto be enlarged and reduced in size (expanded and contracted). In theillustrated embodiment disclosed by way of example, the pushing element66 is an inflatable balloon in the same way of the ureter plug part 32.Through an additional lumen terminated at the pushing element 66 in theelongated member 31, the pushing element 66 is expanded (inflated) byintroducing the fluid into an interior space of the pushing element 66,and the pushing element 66 is contracted (deflated) by allowing thefluid to empty from the ureter plug part 32. The fluid can be water,air, contrast medium, etc. The pushing element 66 has differentcharacteristics from the ureter plug part 32; in the expanded state, theprojections 68 are more shaped (elongated) and more rigid than theureter plug part 32. FIG. 14 illustrates the contracted or deflatedstate of the pushing element 66.

The ureter wall pushing element 66 is beneficial in that it helps ensurethat adequate space exists for flow of the flushing fluid which isgenerally illustrated by the arrow in FIG. 13. That is, the ureter wallpushing element 66 provides a flow path for the fluid (liquid)discharged from the calculus removing/retrieving device as well as thecalculus being washed away by the flushing/washing fluid. The ureterwall pushing element 66 is especially helpful in this regard withrespect to the narrowed ureter lumen such as UBJ 212.

FIGS. 15A and 15B illustrate a calculus removing/retrieving devicerepresenting another example of the device and associated methoddisclosed here. In the earlier embodiments of the calculusremoving/retrieving device, the ureteral plug part 32 is configured toexpand into contact with the lumen 205 of the ureter 204. This versionof the calculus removing/retrieving device 30′″ differs in that theureteral plug part 32′″ is configured to draw or pull, through suctionor vacuum, the inner surface or wall of the ureteral lumen 205 of theureter 204 towards and into contact with the ureteral plug part 32′″.FIG. 15A illustrates an example of the configuration of the ureteralplug part 32′″. The distal end portion of the elongated member 31′″ isprovided with a series of through holes or openings 72 which communicatewith the interior of the elongated member 31′″. The interior of theureteral plug part 32′″ is connected to a suction source or vacuumsource. In the illustrated embodiment, the vacuum or suction source isthe syringe illustrated in FIG. 5. In the embodiment discussed above andillustrated in FIG. 5, the plunger 52 is pushed in the forward directionto inflate the ureteral plug part 32. In this embodiment, the plunger 52is pulled in the rearward direction after the syringe is connected tothe end of the elongated member 31′″ to create a vacuum or suction thatdraws the inner surface of the ureteral lumen 205 towards and intodirect contact with the outer surface of the ureteral plug part 32′″ asillustrated in FIG. 15B. This embodiment thus provides an alternativeway for occluding or closing-off the ureteral lumen 205 in the ureter204. The ureteral plug part 32′″ operates as an aspiration port.

The embodiment described above uses a syringe as a vacuum or suctionsource. But other vacuum or suction sources can be used.

FIGS. 16 and 17 illustrate a calculus removing/retrieving devicerepresenting a further example of the device and associated methoddisclosed here. This embodiment has particularly useful applications forremoving/retrieving calculus located in the renal pelvis (kidney).Generally speaking, the calculus removing/retrieving device 130 isconfigured to occlude or cover one part of the renal pelvis, and at thesame time deliver or discharge washing or flushing fluid (liquid) to theremaining part of the renal pelvis to wash or flush away the calculuslocated in the other uncovered part of the renal pelvis.

Referring to FIG. 16, the calculus removing/retrieving device 130includes an elongated member (main body) 131 and a tubular member orcatheter 172 provided with the irrigation port or irrigation nozzle 134.The elongated member or main body 131 possesses a lumen open at bothends, and the tubular member 172 is axially movable within the lumen ofthe elongated member 131. The tubular member 172 also includes a lumenextending throughout the tubular member and open at both ends. In theillustrated embodiment disclosed by way of example, the irrigation portor irrigation nozzle 134 is the open distal end of the tubular member172. The lumen in the tubular member 172 is connected to a fluid source,an example of which is the fluid source 60 illustrated in FIG. 3.

The lumen in the elongated member 131 (i.e., the space between the outersurface of the tubular member 172 and the inner surface of the elongatedmember 131) communicates with the interior of an expandable andcontractible renal cover part 132 which is fixed to the elongated member131. The renal cover part 132 serves as an occluding means for occludinga portion of the renal pelvis as described in more detail below.

The lumen in the elongated member 131 is connected to a fluid sourcelike the syringe 50 illustrated in FIG. 5. A check valve similar to thatillustrated in FIGS. 3-6 can be employed to control the introduction ofthe fluid (e.g., air/gas) into the expandable/contractible renal coverpart 132. The syringe 50 and the check valve also allow the fluid to bedischarged from the renal cover part 132 as explained above. In theillustrated example, the expandable/contractible renal cover part 132 isan expandable balloon which expands (inflates) when fluid is introducedinto the balloon and contracts (deflates) when fluid is expelled fromthe balloon.

An example of a method for retrieving/removing calculus from a renalpelvis using the calculus removing/retrieving device 130 illustrated inFIG. 17 is as follows. The calculus removing/retrieving device 130 isinserted into the body (e.g., by way of the urethra), passed through thebladder 202, and moved along the ureter 204 until entering the renalpelvis. Throughout this movement of the calculus removing/retrievingdevice 130 and introduction to the renal pelvis, the renal cover part132 is in a deflated/contracted condition, and fluid is not dischargedfrom the irrigation port or irrigation nozzle 134. After positioning therenal cover part 132 in the renal cavity, the renal cover part 132 isexpanded or inflated to occlude or cover a part of the renal pelvis asgenerally illustrated in FIG. 17. After the one part of the renal pelvisis covered or occluded by the expanded renal cover part 132, fluid isdischarged from the irrigation port or nozzle 134 and is directed at theother part of the renal pelvis that is not covered or occluded by therenal cover part 132. This fluid that is discharged from the irrigationport 134 washes out or flushes the uncovered part of the renal pelvis,taking with it the calculus. The calculus 300 and the fluid are thenwashed away or flushed-out by way of the ureter 204.

As a part of carrying out this operation, the irrigation port 134 can bepointed at the uncovered portion of the renal pelvis. This directedapproach can help facilitate the flushing or washing-out of thecalculus.

It is also possible as a part of this medical procedure to uselithotripsy on the calculus located in the renal pelvis before coveringa part of the renal pelvis by inflating the renal cover part 132. Inthis case, lithotripsy is preferably carried out before introducing therenal cover part 132 into the renal pelvis.

The calculus removing/retrieving device 130 illustrated in FIG. 16 canbe delivered to the renal pelvis using a ureteral access sheath and aureteroscope, preferably a flexible ureteroscope. Here, the ureteralaccess sheath is first inserted into the living body and then the device130 is inserted into the ureteroscope, and then the ureteroscope isinserted into the ureteral access sheath. The ureteral access sheath isintroduced into the living body (for example by way of the urethra) andis advanced to a position where the tip end of the ureteral accesssheath is located beyond (i.e., at the upper part or proximal part) theureteropelvic junction. This is favorable positioning to help maintainor keep the flexibility of the tip end of the ureteroscope. Theureteroscope is used to visually observe the progress or movement of thecalculus removing/retrieving device 130 towards the renal pelvis. Oncethe calculus removing/retrieving device 130 is properly positioned inthe renal pelvis, the ureteroscope can be pulled back outside the body.The renal cover part 132 is then inflated to cover the one portion ofthe renal pelvis. In addition, the ureteroscope can be pulled back afterthe one part of the renal pelvis is covered or occluded by the expandedrenal cover part 132. The fluid is discharged from the irrigation portor nozzle 134 to wash out the other part of the renal pelvis. The fluidand the calculus flow through the ureteral access sheath to outside thebody.

FIGS. 18 and 19 illustrate an additional aspect of the calculusretrieving and removing method disclosed here and described above. Thisadditional aspect involves subjecting the calculus to relatively smallpower to move or shift calculus (calculus-moving power orcalculus-position changing power). This power may involve applying smallimpact waves generated when water flows from the irrigation port of theureteroscope, or by vibrating or shaking the bed/table on which thepatient is lying. The objective here is to move calculus from the onepart of the renal pelvis to another part of the renal pelvis. Thismovement of the calculus from the one part of the renal pelvis to theother part of the renal pelvis is schematically illustrated in FIG. 18.The calculus is then collected in one part or region of the renalpelvis. The parts or region at which the calculus is collected ispreferably the minor calyx. After the calculus is collected in the onepart or region of the renal pelvis, the calculus removing/retrievingdevice is introduced into the renal pelvis, and the one part of therenal pelvis from which the calculus was removed or evacuated is coveredby the inflated renal cover part 132 as illustrated in FIG. 19. Theuncovered part of the renal pelvis is then washed or flushed byintroducing fluid (liquid) into the renal pelvis through the irrigationport 134 as described above. Employing this additional aspectillustrated in FIGS. 18 and 19 improves the efficiency of the calculusremoval/retrieval operation in that most or all of the calculus is movedto the area or region of the renal pelvis that is flushed-out by thefluid delivered from the irrigation port or nozzle 134.

FIG. 19 illustrates an additional aspect associated with this embodimentof the calculus retrieval/removal device and method. As shown in FIG.19, a pressure sensor 145 is attached to the calculusremoving/retrieving device 130, specifically the elongated member 131.This pressure sensor 145 senses the pressure in the renal pelvis. Thepressure sensor 145 is connected to a control unit 146 which controlsoperation of the calculus removing/retrieving device 130, including thedischarge of the fluid out of the irrigation nozzle 134. Wheninformation provided by the pressure sensor 145 indicates that theintra-renal pressure (i.e., the pressure inside the renal pelvis) isgreater than a certain pressure (e.g., from 0.2 mH₂O to 0.7 mH₂O, morefavorable, from 0.3 mH₂O to 0.5 mH₂O), the control unit 147 can alertthe high intra-renal pressure to the physician and/or stop dischargingadditional fluid (water) into the renal pelvis.

FIG. 20 illustrates another aspect of the disclosure here. First, therenal cover part 132 is inflated to cover the one portion of the renalpelvis. Then the ureteroscope is pulled back, and simultaneously fluidis discharged from the irrigation port or nozzle 134 to wash out theother part of the renal pelvis. As shown in FIG. 20, to avoid a rise ofthe intra-renal pressure, the volume of “pulling back the ureteroscope”represented by the shaded portion near the arrow in FIG. 20 and the“additional pouring irrigation water” represented by the other shadedportion in FIG. 20, should be continuously adjusted as equal. Throughthis procedure, physician can see the calculus state by ureteroscopeduring washing out.

The calculus removing/retrieving device 130 shown in FIG. 16 can also beused to “rake” out the calculus or stones in a manner similar to thatdescribed above. For example, after the one part of the renal pelvis iscovered or occluded by the expanded renal cover part 132, the fluid thatis discharged from the irrigation port 134 washes out or flushes theuncovered part of the renal pelvis, taking with it the calculus. Thecalculus 300 and the fluid partially can be washed away or flushed-outby way of the ureter 204, but residues (residual calculi) exist in theureter 204. To remove these residual calculi, the renal cover part 132may be deflated or contacted, and moved rearwardly within the ureter 204in the direction toward the bladder 202. Then the renal cover part 132is re-expanded or re-inflated until the surface of the renal cover part132 partially touches the ureter 204. The renal cover part 132 is movedin this way while the renal cover part 132 is in the expanded orinflated state so that the expanded or inflated renal cover part 132pulls along or rakes the calculus or stones 300.

It is also possible to use the calculus removing/retrieving device 130shown in FIG. 16 to “rake” out the calculus or stones in the ureteralaccess sheath when the ureteral access sheath is used. In thissituation, the residual calculus 300 and the fluid exist in the ureteralaccess sheath the same as above. The calculus removing/retrieving device130 is delivered to the lumen of the ureteral access sheath while therenal cover part 132 is deflated or contacted. After reaching thedesired position in the ureteral access sheath lumen, the renal coverpart 132 is expanded (inflated) and then pulled rearwardly within theureteral access sheath lumen to rake-out calculus or stones in theureteral access sheath lumen. In this variation, the extent to which therenal cover part 132 can be expanded or inflated will be dictated by theinner diameter of the ureteral access sheath lumen.

According to another aspect of the disclosure here, when the calculusremoving/retrieving device 130 shown in FIG. 16 is used with aureteroscope, the amount of pull-back or rearward movement of thecalculus removing/retrieving device 130 is controlled according to theamount of water being discharged into the renal pelvis. As explainedabove, it is possible to use a ureteroscope to visually observe themovement of the calculus removing/retrieving device 130 into the renalpelvis. When the calculus removing/retrieving device 130 reaches thedesired position in the renal pelvis, the ureteroscope can bepulled-back before the convection-producing discharge of the fluid intothe renal pelvis or the ureteroscope can be held at its currentposition. In the latter case, as the fluid (wash-out fluid) isdischarged into the renal pelvis, the ureteroscope is pulled-backward,accompanied by the calculus/stones and the wash-out fluid. Thispull-back of the ureteroscope is controlled so that the volume of thepulling-back of the ureteroscope equals the volume of fluid (water)being discharged from the irrigation port 134.

FIGS. 21-24 illustrate a calculus removing/retrieving devicerepresenting a further example of the device and associated methoddisclosed here. This embodiment of the calculus removing/retrievingdevice 330 includes an elongated member 331 provided with an irrigationport or nozzle 334, representing an example of an outlet. An irrigationlumen 336 extends along the elongated member 331. The irrigation lumen336 communicates with the irrigation port or nozzle 334 and alsopossesses an open proximal end. A plunger 376 is movably positioned inthe irrigation lumen 336 to slide along the length of the irrigationlumen. The plunger includes a rubber gasket or plug 378 fixed to theplunger 376 so that the rubber gasket 378 moves together with theplunger 376 as a unit. The gasket 378 fluid-tightly engages the innersurface of the irrigation lumen 336.

The calculus removing/retrieving device 330 also includes a suction port380, representing an example of an inlet. In the illustrated embodimentshown in FIGS. 21 and 22, the suction port 380 is positioned proximallyof the irrigation port 334. A check valve 382 (one-way valve) closes theirrigation port 334, while another check value 384 (one-way valve)closes the suction port 380. The check valve 382 allows fluid to bedischarged from the irrigation lumen 336 to outside the device asillustrated by the arrow 375 in FIG. 21. On the other hand, the checkvalve 382 prevents the fluid from flowing into the irrigation lumen 336in the direction opposite the arrow 375.

Referring to FIG. 21, when the plunger 376 is pushed in the forwarddirection indicated by the direction of the arrow 373 in FIG. 21, fluid(liquid) in the irrigation lumen 336 and positioned ahead of the gasket378 (i.e., on the right side of the gasket 378 in FIG. 21) is dischargedout through the irrigation port 334 by way of the check valve 382. Thecheck valve 382 is configured to permit flow in the direction of thearrow 375 while preventing flow in the direction opposite the arrow 375.

Referring to FIG. 22, when the plunger is pulled rearwardly in thedirection indicated by the direction of the arrow 377 in FIG. 22, asuction or vacuum is created on the distal side of the gasket 378 (i.e.,the right side of the gasket with reference to FIGS. 21 and 22) to drawfluid and calculus into the lumen 336 by way of the check valve 384. Thecheck valve 384 is configured to permit flow in the direction of thearrow 379 while preventing flow in the direction opposite the arrow 379.

The calculus removing/retrieving device 330 shown in FIGS. 21 and 22also includes a retrieval part 386 generally in the form of a housing orenclosure 386. A check valve 390 is provided in the enclosure 388 toseparate the interior of the enclosure 386 and the exterior of theenclosure. When open, the check valve 390 permits communication betweenthe interior of the enclosure 386 and the exterior of the enclosure. Thecheck valve 390 is similar to the check valve 384, but the check valve390 can be opened more easily than the check valve 384. In other words,the closing power of the check valve 390 is less than the closing powerof the check valve 384. Thus, when the plunger is pulled rearwardly inthe direction of the arrow 377 in FIG. 22, the check valve 390 is openedmore widely and/or is opened for a longer period of time than the checkvalve 384. The check valve 390 permits fluid and calculus (kidney stonesor stone fragments) to pass through into the enclosure 388, but thecheck valve 384 permits only the fluid to pass through into the lumen336.

FIG. 23 generally illustrates operational aspects associated with use ofthe calculus removing/retrieving device 330. The irrigation lumen 336that communicates with the irrigation port or nozzle 334 is filled witha fluid (e.g., a liquid such as water, saline, etc.) and then theplunger/gasket 378 is positioned inside the irrigation lumen 336 andmoved in the forward direction toward the irrigation port 334. As theplunger 376 moves in the forward direction indicated by the arrow 373,the fluid inside the irrigation lumen is discharged through theirrigation port 334 by way of the check valve 382 and creates convectionin the renal pelvis as schematically indicated by the arrow 381 in FIG.23. This convection is beneficial because when the calculusremoving/retrieving device is positioned in the renal pelvis, theconvection created by the fluid discharged through the irrigation port334 stirs-up the calculus or stone fragments that are present in therenal pelvis. That is, the calculus is lifted-off of the surface of therenal pelvis and is suspended in the convection, thus helping tofacilitate the retrieval of the calculus. During this forward movementof the plunger 376, the check valve 382 is open while the check valve384 at the suction port and the check valve 390 at the retrieval part386 remain closed.

After the plunger 376 has reached the end of its forward stroke,movement of the plunger 376 stops and the check valve 382 automaticallycloses. Next, the plunger 376 is pulled in the rearward direction toretrieve the calculus that has been stirred-up or lifter by the fluidconvection. This rearward movement of plunger 376 in the direction ofthe arrow 377 causes the check valve 382 to close. As the plunger 376 ispulled in the rearward direction, a vacuum or suction is created infront of the gasket 378. This causes the check valve 384 to open, andcauses the check valve 390 to be wide-opened (more widely-open than thecheck valve 384) so that fluid and calculus or stones in the renalpelvis flow through the check valve 390 and enter the enclosure 388. Thecalculus or stones 300 which have passed though the check valve 390 tendto remain in the enclosure 388 and fall toward the bottom of theenclosure due to their weight, whereas the fluid passing through thecheck valve 390 and entering the enclosure 388 is drawn through the opencheck valve 384, enters the inside of the irrigation lumen 336. If theplunger 376 is pushed and pulled continuously, a relatively stableconvection can be generated in the renal pelvis

FIG. 24 schematically illustrates the calculus removing/retrievingdevice 330 positioned in the renal pelvis of the kidney 200. Asdescribed previously, the calculus removing/retrieving device can beinserted through the urethra, advanced through the bladder and alongureter 204 where it enters the renal pelvis. Once the calculusremoving/retrieving device 330 is properly positioned in the renalpelvis, the plunger 376 is moved in the forward direction to dischargefluid out of the irrigation lumen 336, through the irrigation port ornozzle 334 and into the renal pelvis to create fluid convection asdescribed above. FIG. 24 illustrates the way that the fluid convectionlifts and suspends the calculus 300. During the discharge of the fluidthough the irrigation port 334, the check valve 382 is open while thecheck valve 384 and the check valve 390 remain closed. After the plungerreaches the end of its forward stroke, the plunger is pulled in therearward direction to cause fluid and calculus/stone fragments to bedrawn through the check valve 390 and into the enclosure 388. Thecalculus or stone fragments collect in the enclosure 388 where theygather and are held by virtue of their weight. On the other hand, thefluid that is drawn through the check valve 390 passes through the checkvalve 384 and continues to be drawn along the irrigation lumen 336.During the rearward movement of the plunger, the check valve 384 and thecheck valve 390 are open while the check valve 382 remains closed.

As in the embodiments described above, it is possible to insert thecalculus removing/retrieving device 330 into the living body using aureteroscope, preferably a flexible ureteroscope. The calculusremoving/retrieving device 330 is introduced into the instrument channelof the ureteroscope and is advanced to the renal pelvis while beingobserved through operation of the ureteroscope.

As an alternative to the configuration of the calculusremoving/retrieving device 330 shown in FIGS. 21 and 22, it is possibleto do away with the retrieval part 386 of the calculusremoving/retrieving device 330. In this alternative, the ureteroscope isused in the manner described above to visually observe the forwardmovement of the calculus removing/retrieving device toward the renalpelvis. Once the calculus removing/retrieving device is appropriatelypositioned in the removing/retrieving device, the ureteroscope is pulledback to the ureteropelvis junction 208 (shown in FIG. 1) or into theureter 204 (shown in FIG. 1). This creates a space between the distalend of the ureteroscope and the ureteral inner wall. The calculus/stonefragments are then collected in this space formed by the tip end of theureteroscope and the ureteral inner wall when the ureteroscope is pulledback, instead of the retrieval part 386. The calculus/stone fragmentstogether with the fluid enter this space and flow along the ureter tothe bladder or outside the body. As explained above, a continuouspushing and pulling procedure is necessary to generate the stableconvection in the renal pelvis and maintain the renal pelvis capacity.

FIGS. 25A and 25C illustrate a rubber seal check valve which can be usedas a specific form of the check valve 382, 384 in the calculusremoving/retrieving device 330. The rubber seal check valve includes arubber element 392 secured to the elongated member 331. The rubberelement 392 covers a plurality of holes or through openings 394 in theelongated member 331. The rubber element 392 is secured to the elongatedmember 331 in any appropriate way so that the rubber element 392normally covers the holes or through openings 394. When pressure isapplied from the side opposite the rubber element 392, the rubberelement 392 is lifted as shown in FIG. 25C to allow fluid to dischargeor pass through the holes 394.

Thus, if the rubber seal check valve is used for the valve 382 shown inFIGS. 21 and 22, the valve would take the position shown in FIG. 25Cwhen the plunger 376 is pushed in the forward direction and would takethe position shown in FIG. 25B when the plunger 376 is pulled in therearward direction. If the rubber seal check valve is used for the valve384 shown in FIGS. 21 and 22, the valve would be in the position shownin FIG. 25B when the plunger 376 is moved in the forward direction andwould move to the position shown in FIG. 25C when the plunger 376 ispulled in the rearward direction.

FIG. 26 illustrates known duck bill-type valves which can be used asanother specific form of the check valve 382, 384 in the calculusremoving/retrieving device 330. If the duck bill-type valves is used forthe valve 382 shown in FIGS. 21 and 22, the narrowed mouth of the duckbill-type valve would open when the plunger 376 is pushed in the forwarddirection and would return to the closed position when the plunger 376is pulled in the rearward direction. If the duck bill-type valve is usedfor the valve 384 shown in FIGS. 21 and 22, the narrowed mouth of theduck bill-type valve would open when the plunger 376 is pulled in therearward direction and would return to the closed position when theplunger 376 is pushed in the forward direction.

FIG. 27 illustrates an example of an impeller which can also be employedin the calculus removing/retrieving device 330. Instead of the plunger376 pushing and pulling action (movement) in the lumen 336 equipped withthe oppositely-oriented check valve arrangement, mechanically rotatingthe impeller can create the objective convection in the renal cavity.

The detailed description above describes a device and method forretrieving/removing calculus from parts of a living body such as theureter and the renal pelvis. The invention is not limited, however, tothe precise embodiments and variations described. Various changes,modifications and equivalents can effected by one skilled in the artwithout departing from the spirit and scope of the invention as definedin the accompanying claims. It is expressly intended that all suchchanges, modifications and equivalents which fall within the scope ofthe claims are embraced by the claims.

What is claimed is:
 1. A method of retrieving calculus in a renal pelviscomprising: moving an elongated member toward the renal pelvis, theelongated member including an outlet, an inlet and a retrieval part at adistal side of the elongated member; positioning the outlet and theinlet of the elongated member in the renal pelvis; producing fluid flowin the renal pelvis by suctioning fluid from the inlet and exhaustingthe fluid out of the outlet, the fluid being displaced from an outsideof the retrieval part, and into and through the retrieval part, whilethe calculus located in the renal pelvis enters the retrieval part andremains in the retrieval part; and withdrawing the elongated member fromthe renal pelvis while the calculus is in the retrieval part afterretrieving the calculus by way of the retrieval part.
 2. The method ofclaim 1, further comprising inserting the elongated member into a lumenof an ureteroscope and advancing the elongated member and theureteroscope together to position the outlet and the inlet in the renalpelvis.
 3. The method of claim 1, wherein the elongated member includesan occluding part located proximal of the inlet, and wherein the renalpelvis is connected to a ureter possessing a ureteral lumen, the methodfurther comprising occluding the ureteral lumen by way of the occludingpart and filling-up the renal pelvis by injecting the fluid into therenal pelvis after occluding the ureteral lumen.
 4. The method of claim1, wherein the renal pelvis is connected to a ureter possessing aureteral lumen, the method further comprising occluding the ureterallumen at a position proximal of the outlet and the inlet and filling-upthe renal pelvis by injecting the fluid into the renal pelvis afteroccluding the ureteral lumen.
 5. The method of claim 1, furthercomprising a plunger positioned in a lumen of the elongated member, themethod further comprising moving the plunger within the lumen of theelongated member to eject fluid from the outlet and moving the plungerwithin the lumen of the elongated member to suck fluid from the inlet inthe elongated member and produce the fluid flow in the renal pelvis. 6.The method of claim 1, further comprising a plunger positioned in alumen of the elongated member, wherein the retrieving of the calculuscomprises moving the plunger within the lumen of the elongated member tocreate suction from the inlet that draws the calculus into the retrievalpart.
 7. The method of claim 1, further comprising a plunger positionedin a lumen of the elongated member, the method further comprising movingthe plunger within the lumen of the elongated member to eject fluid fromthe outlet and to suck fluid from the inlet in the elongated member andproduce the fluid flow in the renal pelvis.
 8. The method of claim 1,further comprising a plunger positioned in a lumen of the elongatedmember, the plunger possessing a sealing part in sealing contact with aninner surface of the lumen in the elongated member, the method furthercomprising moving the plunger within the lumen of the elongated memberto eject fluid from the outlet in the elongated member and produce thefluid flow in the renal pelvis.
 9. The method of claim 1, furthercomprising a plunger positioned in a lumen of the elongated member, theplunger possessing a sealing part in sealing contact with an innersurface of the lumen in the elongated member, wherein the retrieving ofthe calculus comprises moving the plunger within the lumen of theelongated member to create suction from the inlet that draws thecalculus into the retrieval part.
 10. The method of claim 1, wherein theretrieval part is configured to allow the fluid to pass through and tocatch the calculus, wherein the retrieving of the calculus includescapturing the calculus present in the fluid flow at the retrieval part.11. The method of claim 1, wherein both the outlet and the inlet areconfigured to allow fluid to pass through the outlet and the inlet inonly one direction, and an amount of the fluid exhausted from the outletand an amount of the fluid suctioned from the inlet is substantiallyequal, and wherein the producing of the fluid flow in the renal pelvisis carried out while maintaining the amount of the fluid of the renalpelvis.
 12. The method of claim 1, further comprising a rotating memberlocated in a lumen of the elongated member and between the retrievalpart and the outlet, and wherein the producing of the flow from theinlet to the outlet comprises rotating the rotating member andretrieving the calculus in the renal pelvis.
 13. The method of claim 12,wherein the rotating member is an impeller.
 14. A method of retrievingcalculus in a renal pelvis of a living body comprising: positioning anenclosure in the renal pelvis; creating convection in the renal pelvisby circulating liquid in the renal pelvis to lift the calculus from asurface of the renal pelvis; retrieving the calculus in the renal pelvisusing a retrieving part in the enclosure while the enclosure is locatedin the renal pelvis so that the calculus is drawn into the enclosure;and withdrawing the enclosure from the renal pelvis while the calculusis in the enclosure.
 15. The method of claim 14, wherein the creating ofthe convection in the renal pelvis comprises continuously circulatingliquid in the renal pelvis to lift the calculus from the surface of therenal pelvis.
 16. The method of claim 14, wherein the enclosure is fixedto an elongated member so that the enclosure moves together with theelongated member, the elongated member possessing a lumen in which ispositioned a plunger, the lumen also containing the liquid that isintroduced into the renal pelvis, the creating of the convection in therenal pelvis comprising moving the plunger in the lumen.
 17. The methodof claim 14, further comprising an impeller located in a lumen of anelongated member, the creating of the convection in the renal pelviscomprising driving the impeller.
 18. The method of claim 14, furthercomprising inserting the enclosure into a lumen of an ureteroscope andadvancing an elongated member and the ureteroscope together to positionthe enclosure in the renal pelvis.
 19. The method of claim 14, whereinthe introducing of the liquid into the renal pelvis further comprisespassing the liquid through a check valve which permits the liquid topass through the check valve in one direction and to be introduced intothe renal pelvis while also preventing the liquid in the renal pelvisfrom passing through the check valve in a direction opposite the onedirection.
 20. The method of claim 14, wherein the enclosure is fixed toan elongated member so that the enclosure moves together with theelongated member, the elongated member possessing a lumen, wherein theintroducing of the liquid into the renal pelvis includes introducingliquid that is located in the lumen of the elongated member.
 21. Amethod of retrieving calculus in a renal pelvis comprising: moving anelongated member toward the renal pelvis, the elongated member includingan outlet, an inlet and a retrieval part at a distal side of theelongated catheter; positioning the outlet and the inlet of theelongated member in the renal pelvis; producing fluid flow in the renalpelvis by suctioning fluid from the inlet and exhausting the fluid outof the outlet; retrieving the calculus located in the renal pelvis byway of the retrieval part; withdrawing the elongated member from therenal pelvis after retrieving the calculus by way of the retrieval part;the retrieval part being configured to allow the fluid to pass throughand to catch the calculus; and the retrieving of the calculus includingcapturing the calculus present in the fluid flow at the retrieval part.